A significant amount of work has been performed over the past 2 years furth
er defining the pathophysiology of juvenile idiopathic arthritis (JIA). The
development of the biologic agent etanercept represents successful transla
tional research. This genetically engineered fusion protein targets tumor n
ecrosis factor, binding and inactivating this important component of inflam
mation. This advance has been accompanied by refinements in classification,
as well as further elucidation of the natural disease course of JIA. Recen
t work continues to demonstrate the widespread nature of JIA, as well as it
s severity in adulthood. (C) 2001 Lippincott Williams & Wilkins, Inc.